1. Field of the Invention
The present invention relates to a display apparatus and method, and more particularly, to a display apparatus and method for selectively displaying a two-dimensional image and a three-dimensional image.
2. Description of the Related Art
With rapid changes in human life, such as an increase in demand for jobs using the Internet, realistic communication, virtual reality, and an endoscope, a need of integrating a computer, broadcasting, and communication into a single medium for primarily visualizing multimedia technology, and visualization of the results of diagnosis and measurement in three-dimensional images, demand for a display apparatus which can display an image in three dimensions is increasing.
Three-dimensional display technology is required in the fields of three-dimensional display used as a new medium of advertisement, three-dimensional multimedia image display terminals used at home, image display terminals for simulators and educational training, image display terminals for visualizing various types of precision measurements and diagnoses, medical three-dimensional image display terminals, image display terminals for monitoring and controlling, three-dimensional image monitors for video conferencing and advertisement, three-dimensional televisions for broadcasting, image display terminals and/or various types of parts used for constructing special environments for education/pleasure, image apparatuses for three-dimensional games, and head-up display for airplanes and automobiles.
Technology of designing and manufacturing a structure of an optical plate such as a lenticular plate or a microlens plate to form a visual field and driving control technology for reproducing a pixel pattern corresponding to the visual field on a display device are required to implement a general three-dimensional display apparatus. Multiple viewpoint display is a technology of displaying a three-dimensional image using binocular parallax by displaying different view images. A lenticular method and an Integral Photography (IP) method are multiple viewpoint display methods.
FIG. 1 shows a pixel structure and a disposition of a lenticule in a 7-viewpoint three-dimensional display apparatus disclosed in WO Patent Publication No. 99/5559. It illustrates an example of a lenticular method.
Referring to FIG. 1, in the conventional 7-viewpoint three-dimensional display apparatus, a lenticular plate 1 is disposed above an array of RGB sub-pixels 3 constituting a single color pixel such that lenticules 1a slant on the array of RGB sub-pixels 3 in order to accomplish horizontal and vertical parallax.
FIG. 2 shows a microlens plate used in the IP method. In the IP method, an image is photographed via the microlens plate 5 shown in FIG. 2. The photographed image is displayed using a flat panel display such as a liquid crystal display (LCD), and the displayed image is viewed via another microlens plate having similar characteristics as the microlens plate 5 used during photographing.
In the IP method, each lens 5a of the microlens plate 5 photographs a whole image of an object viewed from its position within the microlens plate 5. Accordingly, the microlens plate 5 functions as if many cameras are arranged in two dimensions. Such function of the microlens plate 5 is disclosed by F. Okano et al. in “Applied Optics”, Vol. 36, pp. 1598-1603, 1997.
However, the conventional 7-viewpoint three-dimensional display apparatus using a lenticule method and the conventional three-dimensional display apparatus using the IP method have the following problems.
In the 7-viewpoint three-dimensional display apparatus shown in FIG. 1, since it is difficult to independently and separately drive the RGB sub-pixels 3, it is difficult to display real images in real time.
In the IP method using the microlens plate 5, as shown in FIG. 2, vertical and horizontal parallaxes are simultaneously indicated and a volume image is displayed. Because a whole image of an object must be recorded on a single microlens 5a, however, development of a display device which can display the whole image of the object in an area corresponding to the diameter of the microlens 5a at a predetermined resolution is required. However, it is difficult to manufacture the microlens plate 5 having a high resolution, and a space among the microlenses 5a causes an image to be discontinuous. In addition, a border line between microlenses 5a causes distortion or deformation. As a result, a ghost phenomenon of overlapping images occurs when a three-dimensional image is reproduced.
Moreover, the conventional 7-viewpoint three-dimensional display apparatus using the lenticule method and the conventional three-dimensional display apparatus using the IP method are suitable for three-dimensional image display but have problems in displaying two-dimensional images. Accordingly, they are expensive and not suitable to the market, and thus have very low practical usability because most contents are suitable to a two-dimensional mode and contents for a three-dimensional mode are not common at present.